1. Field of the Invention
The present invention relates to an apparatus and method for applying surgical staples to attach objects to body tissue. More particularly, this invention relates to a staple applier particularly adapted for attaching surgical mesh to body tissue to reinforce a surgical repair of the body tissue, as in hernia repair.
2. Background of the Invention
Hernias may be divided into three general classes: direct hernia, indirect hernia and femoral hernia. In a direct or indirect inguinal hernia, often a part of the intestine protrudes through a defect in the supporting abdominal wall to form a hernial sac requiring surgery which generally includes a surgical incision in the groin ranging up to six inches in length. Several layers of the abdominal wall are generally separated to reach the herniated portions. During the procedure, the hernia is closed outside the abdominal wall in a manner which resembles the tying of a sack at the neck. Often a surgical mesh is attached by sutures directly over the hernia repaired opening to provide a reinforcement to the opening.
Traditionally, such hernia repairs involved major invasive surgical procedures which often caused excessive trauma to the patient and necessitated unusually long post-operative recuperative periods. In addition, numerous complications, related directly or indirectly to the surgery often resulted, including bleeding, infection, testicular atrophy, organ damage, nerve damage, blood vessel damage, etc. Further, cutting through the numerous layers of tissue to obtain access to the herniated area often caused severe trauma to the patient. A detailed discussion of traditional hernia repair may be found in "Hernia Repair Without Disability, Second Edition" by Irving L Lichtenstein.
Such invasive surgical procedures have also been utilized in other areas of the body, including surgery on the gall bladder, appendix, lungs and the like. For the reasons previously stated, the use of laparoscopic and endoscopic surgical procedures have been relatively popular and such popularity has provided additional incentive to develop the procedures further.
In laparoscopic procedures, surgery is performed in the interior of the abdomen through a small incision; in endoscopic procedures, surgery is performed in any hollow viscus of the body through narrow endoscopic tubes inserted through small entrance wounds in the skin. Laparoscopic and endoscopic procedures generally require that any instrumentation inserted into the body be sealed, i.e., provisions must be made to ensure that gases do not enter or exit the body through the laparoscopic or endoscopic incision as, for example, in surgical procedures in which the surgical region is insufflated. Moreover, laparoscopic and endoscopic procedures often require the surgeon to act on organs, tissues and vessels far removed from the incision, thereby requiring that any instruments be used in such procedures be long and narrow while being functionally controllable from one end of the instrument, i.e. the proximal end.
In hernia surgery, as compared to gall bladder surgery, certain procedures and instruments are the same, yet certain of the instrument requirements differ. For example, in hernia surgery a suitable mesh material is generally sutured over the opening in the tissue. The mesh material is often also attached by sutures and left within the opening to act as a reinforcing agent for tissue regrowth in the area of the surgery. One example of a mesh material currently utilized in hernia surgery includes a polypropylene material marketed by the Ethicon division of Johnson & Johnson, New Brunswick, N.J., under the trademark MARLEX. Another example of a mesh material is a tri-fluoroethylene material marketed by W. L. Gore & Associates, Newark, Del., under the trademark GORE-TEX.
As noted, during conventional invasive surgical procedures, such mesh materials are often sutured within the surgical opening or over the sutured opening by conventional suturing techniques. However, with the advent of laparoscopic surgery the need for suitable mesh attachment techniques through the relatively narrow endoscopic tubes or cannulas is clearly defined. Up to the present, such devices or staples suitable for mesh attachment have not yet been developed.
U.S. Pat. No. 4,944,443 to Oddsen et al. discloses an instrument and method for applying and forming staples into body tissue to suture a hernial opening. The staple is applied to two pieces of body tissue on opposite sides of the opening which are gripped, approximated and held together by a tissue positioning assembly. U.S. Pat. No. 4,919,152 to Ger relates to a surgical instrument for placing a single clip which is proposed for use in direct hernia repair for closing sacs having narrow neck openings.
Up to the present there remains a need for an apparatus which is particularly adapted to endoscopicaily apply staples for attaching objects such as surgical mesh to body tissue in a manner to positively secure the object to the body tissue without danger of separation thereof after the attachment is completed. The present invention relates to such an apparatus as well as a method for attaching such objects with staples particularly configured and adapted to accomplish these objectives.